Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. Chanting “Allahu Akbar” (God is greatest), dozens of armed men in camouflage uniforms from Russia's republic of Chechnya train in snow in a camp in the rebel-held east Ukraine. They say their “Death” unit fighting Ukrainian forces has 300 people, mostly former state security troops in the mainly-Muslim region where Moscow waged two wars against Islamic insurgents and which is now run by a Kremlin-backed strongman. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion stand in a line during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion walk during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

A Pro-Russian separatist from the Chechen “Death” battalion takes part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion run during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion walk during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion walk during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion run during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

A pro-Russian separatist from the Chechen “Death” battalion takes part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion run during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)

One of the pro-Russian separatist leaders from the Chechen “Death” battalion, identified as his nickname “Stinger”, speaks during a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. (Photo by Maxim Shemetov/Reuters)